package com.example.lotterysystem.service.activitystatus.impl;

import com.example.lotterysystem.common.errorcode.ServiceErrorCodeConstants;
import com.example.lotterysystem.common.exception.ServiceException;
import com.example.lotterysystem.dao.mapper.WinningRecordMapper;
import com.example.lotterysystem.service.ActivityService;
import com.example.lotterysystem.service.activitystatus.ActivityStatusManger;
import com.example.lotterysystem.service.activitystatus.operater.AbstractActivityOperator;
import com.example.lotterysystem.service.dto.ConvertActivityStatusDTO;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import org.springframework.util.CollectionUtils;

import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;

@Service
public class ActivityStatusMangerImpl implements ActivityStatusManger {

    private static final Logger logger = LoggerFactory.getLogger(ActivityStatusMangerImpl.class);


    @Autowired
    private final Map<String, AbstractActivityOperator> operatorMap = new HashMap<>();

    @Autowired
    private ActivityService activityService;



    @Override
    @Transactional(rollbackFor = Exception.class)
    public void handlerEvent(ConvertActivityStatusDTO convertActivityStatusDTO) {
        // 1、活动状态扭转对顺序有依赖性，导致代码维护性差
        // 2、状态转条件可能会扩展，当前写法的扩展性和维护性较差

        if (CollectionUtils.isEmpty(operatorMap)) {
            logger.warn("operatorMap 为空！");
            return;
        }

        Map<String, AbstractActivityOperator> currMap = new HashMap<>(operatorMap);
        Boolean update = false;

        // map<String, AbstractActivityOperator>

        // 先处理人员、奖品
        update = processConvertStatus(convertActivityStatusDTO, currMap, 1);

        // 后处理活动
        update = processConvertStatus(convertActivityStatusDTO, currMap, 2) || update;

        // 更新缓存
        if (update) {
            activityService.cacheActivity(convertActivityStatusDTO.getActivityId());
        }

    }

    @Override
    public void rollbackHandlerEvent(ConvertActivityStatusDTO convertActivityStatusDTO) {
        // operatorMap : 活动、奖品、人员
        // 活动是否需要回滚？  绝对要！
        // 原因：奖品都恢复成 INIT， 那么这个活动下的奖品就还没抽完
        for (AbstractActivityOperator operator : operatorMap.values()) {
            operator.convert(convertActivityStatusDTO);
        }

        // 缓存更新
        activityService.cacheActivity(convertActivityStatusDTO.getActivityId());
    }

    private Boolean processConvertStatus(ConvertActivityStatusDTO convertActivityStatusDTO,
                                         Map<String, AbstractActivityOperator> currMap,
                                         int sequence) {
        Boolean update = false;
        // 遍历 currMap
        Iterator<Map.Entry<String, AbstractActivityOperator>> iterator = currMap.entrySet().iterator();
        while (iterator.hasNext()) {
            AbstractActivityOperator operator = iterator.next().getValue();
            // Operator 是否需要转换
            if (operator.sequence() != sequence
                || !operator.needConvert(convertActivityStatusDTO)) {
                continue;
            }
            // 需要转换
            if (!operator.convert(convertActivityStatusDTO)) {
                logger.error("{}状态转换失败！", operator.getClass().getName());
                throw new ServiceException(ServiceErrorCodeConstants.ACTIVITY_STATUS_CONVERT_ERROR);
            }

            // currMap 删除当前 Operator
            iterator.remove();
            update = true;
        }
        return update;
    }
}
